Organo tin compounds and compositions containing same



United States Patent ORCANO TIN COMPOUNDS AND COMPOSITIONS CONTAINING SAME Ernest W. Johnson, Westfield, N.J., assign'or to Metal & Thermit Corporation, New York, N. a corporation of New Jersey No Drawing. Original application July 7, 1951, Serial No. 235,674, now Patent No. 2,801,258, dated July 30, 1957. Divided and this application June 29, 1955, Serial No. 521,646

16 Claims. (Cl. 260-318) This application is a division of Serial No. 235,674, which has now matured into Patent No. 2,801,258, issued July 30, 1957. The present invention relates to a new organotin mercaptide compound, the method of making the same and a resin composition containing the organotin mercaptide as a stabilizer.

In accordance with the present invention, a new compound has been developed classified as an organotin mercaptide and having the formula R,,Sn(SR') in which R is a group of the class consisting of an alkyl, aryl and heterocycle in substituted and unsubstituted form, R is a group of the class consisting of alkyl, aryl and heterocycle in substituted and unsubstituted form and n is a number from one to three. The R groups and the R groups need not all be the same.

The organotin mercaptide of the present invention is particularly useful as a stabilizer for vinyl resin and is also useful as a rubber accelerator, rubber anti-oxidant, lube oil additive and polymerization accelerator. In connection with vinyl resin, it has been found that the organotin mercaptide of the character described when added to the vinyl resin in amounts equivalent to 0.5 to 10.0 parts by weight of stabilizer to 100 parts of the resin is effective as a stabilizer. However, for commercial use, 1.0 to 3.0 parts by weight of stabilizer to 100 parts by weight of resin is preferred.

I have found that organotin oxides (R SnO), organotin hydroxides (R SnOH) and stannoic acids (RSnO H) will react with primary, secondary and tertiary mercaptans to yield derivatives of the types R Sn(SR)- R SnSR' and RSn(SR) The reactions for such preparations are as follows:

In accordance with another process for preparing these derivatives, the starting material is an organotin halide. It has been determined in accordance with the present invention, that organotin halides such as R SnX, R SnX and RSnX will react with mercaptan in the presence of basic HCl acceptors, such as alkali metal and alkaline earth metal oxides, hydroxides, bicarbonates and carbonates, and specifically sodium hydroxide or sodium carbonate to yield the same types of derivatives through the replacement of the halide group by the SR group.

The following examples illustrate certain ways in which the organotin mercaptide of the present invention can be prepared:

EXAMPLE I drawn by use of a Barrett moisture trap. After the 2,891,922 Patented June 23, 1959 theoretical water was removed, toluene was removed by a downward vacuum distillation. The final pot temperature was C. and the final pressure was 10 mm. of Hg. The product weighed 85.5 g. and by analyses contained 33.5% Sn and 16.9% S.

EXAMPLE II One-half mole of normal butyl mercaptan, one-quarter mole of dibutyltin oxide and 200 ml. of toluene were heated to reflux. The water of reaction was removed by the use of a moisture trap. Solution of the oxide occurred before all the water was removed. After removal of the water, toluene was stripped out by use of a downward vacuum distillation to yield a final nearly odorless residue. This liquid residue weighed 99.7 g. and contained 28.7% Sn and 15.0% S.

EXAMPLE III One-half mole of isobutyl mercaptan, 0.25 mole of dibutyltin oxide and 200 m1. of toluene were refluxed with stirring until solution of the oxide occurred and the theoretical water was obtained. The toluene was vacuumstripped to leave a light colored liquid product which analyzed 28.8% tin and 15.2% sulfur.

EXAMPLE IV One-half mole of n-amyl mercaptan, 0.25 mole of dibutyltin oxide and 200 ml. of toluene were heated (with mechanical stirring) to reflux. The oxide was completely dissolved after 20 minutes of heating (temperature had only reached 91 C.), while the water was distilling over into a Barrett moisture trap. After the theoretical water (4.5 ml.) was removed, heating was continued for 2.5 hours. The solution was then cooled, filtered and stripped of solvent to a pot temperature of C. at a pressure of 2 mm. The product was a light colored liquid weighing 106.9 grams. Analysis indicated 26.9% Sn; 14.6% S.

EXAMPLE VI 0.088 mole of triphenyltin hydroxide, 0.088 mole of predominately lauryl mercaptan, hereinafter referred to as lauryl mercaptan, Hooker (Hooker Electrochemical Companys product which approximates C13H27SH, being a mixture of normal C C C C mercaptans, with C predominating) and 50 ml. of toluene were heated (stirring) to reflux. After removal of the water of reaction, the mixture was cooled, filtered and filtrate stripped of solvent. The product weighing 37.8 grams contained 18.9% Sn and 6.0% S.

EXAMPLE VII One-half mole of n-amyl-mercaptan, 0.25 mole of dilauryltin oxide and ml. of toluene were heated and stirred at reflux. After the water was removed, the mixture was cooled, filtered and stripped. The product was a light colored liquid weighing 80.2 grams, contained 17.4% Sn and 9.6% S.

EXAMPLE VIII One-half mole of n-hexyl mercaptan, 0.25 mole of dibutyltin oxide and 200 m1. of toluene were heated to reflux. After the water of reaction was removed, the mixture was stripped of solvent. A residual light colored liquid was obtained in 97% yield. Analysis showed 25.2% Sn and 13.5% S.

EXAMPLE IX One mole of ter-hexyl mercaptan 0.5 mole of dibutyl tin oxide and 400 ml. of toluene were heated to reflux. After the theoretical water was removed, the product was filtered hot to remove an insoluble precipitate (weight, 24.6 g.; analysis, 44.9% Sn). After vacuum stripping and cooling, the filtrate deposited 25.0 grams of a solid which was filtered 01f. This solid contained 42.28% Sn. The final filtrate was a light tan liquid weighing 143.9 grams. Analysis indicated 23.4% Sn.

EXAMPLE X One-half mole of n-heptyl mercaptan, 0.25 mole of dibutyltin oxide and 200 ml. of toluene were heated to reflux, the water of reaction removed, and the mixture filtered. After stripping to a temperature of 115 C. and a pressure of 2.5 mm., the filtrate left a very light colored liquid residue (125.2 grams) which analyzed 23.8% Sn and 12.6% mercapto sulfur.

EXAMPLE XI One-half mole n-octyl mercaptan, 0.25 mole of dibutyltin oxide and 200 ml. of toluene were treated as in Example X. The product was a light colored viscous liquid weighing 135.9 g. The theoretical yield is 130 grams. The extra 5.9 grams arise from the mercaptan used. Most of the mercaptans used in this specification were assayed by an iodimetric titration and a quantity of the assayed mercaptan sufficient to give the desired mole quantity of titratable mercapto group (equivalent to the organotin compound) was then taken. Thus, the n-octyl mercaptan used above assayed 89.2% titratable mercaptan. A weighed quantity was taken, sufiicient to contain just one-half mole of titratable SH. Analysis of the product indicated 21.5% Sn and 11.6% S.

EXAMPLE XII Dibutyltin oxide (0.162 mole, 40.3 grams), n-nonyl mercaptan (99.5% by assay; 0.325 mole; 52.0 grams), and toluene (170 ml.) were treated as described in Example X. The product weighed 85.5 grams and contined 21.5% Sn and 11.2% S.

EXAMPLE XIII Dibutyltin oxide (0.25 mole, 62.1 grams), n-decyl mercaptan (94.1% by assay; 0.5 mole; 92.6 grams), and toluene (200 ml.) were allowed to react as described in Example X. The product weighted 149 grams; it was a viscous light colored liquid containing 19.5% Sn and 10.6% S.

EXAMPLE XIV Dibutyltin oxide (0.5 mole, 124.4 grams), 1auryl mercaptan, Hooker (1.0 mole; 216.0 grams), and 200 ml. of toluene were treated as described in Example X. The product weighed 324.3 grams. It was a clear colorless liquid containing 18.0% Sn and 8.4% S.

EXAMPLE XV One mole, 202.0 grams, of tertiary lauryl mercaptan in 100 ml. of toluene was added to 40 grams (1 mole) of sodium hydroxide in 50 ml. of water. To this mixture was added 0.5 mole (151.8 grams) of dibutyltin dichloride in 200 ml. of toluene. The mixture was stirred and heated to distill out the water azeotropically. After removal of the water, the solution was filtered hot to remove the sodium chloride formed (the NaCl forms large crystals in this process). The filtrate was cooled, filtered, and vacuum stripped to remove solvent. At a final temperature of 130 C. at 3 mm. pressure, product was a light colored liquid weighing 287.7 grams. Analysis indicated 18.7% Sn, trace of Cl.

EXAMPLE XVI 91.1 grams of dibutyltin dichloride and 127.7 grams of 1auryl mercaptan, Hooker were heated to 65 C.

in a stirred stainless steel beaker and 42 grams of anhydrous sodium carbonate was added over a 6-minute period. The temperature rose to 83 C. during this time and was held there for 1%. hours. The mixture was filtered, and the product was a clear light colored liquid. Analysis showed 18.0% Sn, 9.7% S, 0.05% Cl.

EXAMPLE XVII One-half mole of lauryl mercaptan, Hooker, 0.25 mole of dimethyltin oxide, and ml. of toluene were refluxed and treated as in Example X. The product was a light colored liquid with an analysis of 19.7% Sn and 10.7% S.

EXAMPLE XVIII One and one-half moles of lauryl mercaptan, Hooker, 0.5 mole of methylstannoic acid and 200 ml. of toluene were used in the process of Example X. The product was a light colored liquid, weighed 360.7 g. and contained 15.0% Sn and 12.0% S.

EXAMPLE XIX One-quarter mole of laury1 mercaptan, Hooker, 0.25 mole of trimethyltin chloride and 100 ml. of toluene are heated to 65 C. as in Example XVI. Anhydrous sodium carbonate (53 grams) is then added to the mixture. Caution: This reaction must be carried out in an efficient hood as the trimethyltin chloride is very noxious. The reaction mixture is filtered hot and stripped of solvent.

EXAMPLE XX One-half mole of lauryl mercaptan, Hooker, 0.25 mole of diphenyltin oxide and 200 ml. of toluene are treated as described in Example X.

EXAMPLE XXI One-quarter mole of triphenyltin chloride, one-quarter mole of lauryl mercaptan, Hooker, 100 ml. of toluene and 53 grams of sodium carbonate are treated as described in Example XIX.

EXAMPLE XXII Diamyltin oxide (0.122 mole, 37.6 grams), 0.244 mole of lauryl mercaptan, Hooker and 100 ml. of toluene were treated as described in Example X. The clear light colored liquid product weighed 70.6 grams and analyzed 17.0% Sn and 8.7% S.

EXAMPLE XXIII One-quarter mole of dilauryltin oxide and 0.5 mole of lauryl mercaptan, Hooker yielded 212.6 grams of light colored liquid product. Analysis indicated 13.0% Sn and 6.9% S.

EXAMPLE XIHV One-half mole of methyltin trichloride, 1.5 moles of lauryl mercaptan, Hooker, 200 ml. of toluene and 318 grams of anhydrous sodium carbonate are treated as described in Example XIX.

EXAMPLE XXV mole of 1auryl mercaptan, Hooker plus 2 moles of Na CO and 150 ml. of toluene were used as in the process of Example XVI. The product weighed 172.3 g. and contained 13.9% Sn and 11.9% S.

EXAMPLE XXVHI One-quarter mole of ethylstannoic acid, 0.75 mole of lauryl mercaptan, Hooker and 150 ml. of toluene are treated by the process of Example X.

EXAMPLE XXIX One-eighth mole of diphenyltin oxide, one-quarter mole of benzylmercaptan and 100 ml. of toluene were treated by the process of Example X. The product contained 22.4% Sn and 12.4% S.

EXAMPLE )GQC One-quarter mole of dilauryltin oxide, one-half mole of benzylmercaptan and 150 ml. of toluene were used in the process of Example X. The product contained 16.1% Sn and 9.2% S.

EXAMPLE XXXI Dibutyltin oxide, 41 grams, n-tetradecyl mercaptan (88.6% SH), 85.5 grams, and 150 ml. of toluene were carried through the process of Example X. The product analyzed 15.7% Sn and 8.85% S, and weighed 123 grams.

EXAMPLE XXXII Dibutyltin oxide, 40.8 grams, n-hexadecyl mercaptan (95.2%), 88.8 grams and 145 ml. of toluene were treated as in Example X. The product weighed 126 grams. An-

alysis indicated Sn, 15.1%; S, 8.3%.

EXAMPLE XXXIII Dibutyltin oxide (0.38 mole) ter-hexadecyl mercaptan (0.76 mole) and 350 ml. of toluene were treated by the process of Example X. Product weighed 265.2 grams; analysis showed Sn, 14.8%.

EXAMPLE XXXIV Dibutyltin oxide (0.25 mole), thiophenol (0.50 mole) and 200 ml. of toluene were treated as in Example X.

The product was a colorless liquid, weighing 110.5 grams. Analysis showed 26.4% Sn.

EXAMPLE XXXV Dibutyltin oxide (0.218 mole), p-thiocresol (74%, 0.435 mole, 73 grams), and 150 ml. of toluene were treated as described in Example X. The light colored liquid product weighed 104.6 grams and contained 23.9% Sn and 13.45% S.

EXAMPLE XPOCVI EXAMPLE XXXVII Dibutyltin oxide (0.5 mole), 2-mercaptobenzthiazole (1 mole) and 350 ml. of toluene were treated as previously described. The product was a light tan solid weighing 275 g. Analysis showed 21.0 Sn and 22.2% sulfur (by combustion). Recrystallization from 50/50 alcohol/acetone yielded a light colored crystalline prodnot.

A general test method was used to test effectiveness of most of the products from Examples I-XXXVII as stabilizers for polyvinyl chloride resins. The resin used was Geon 101 (produced by the B. F. Goodrich Co.) unless otherwise specified.

The stabilizer was incorporated into a mixture of 100 parts by weight of resin and 50 parts by weight of a plasticizer (here Flexol DOP (dioctyl phthalate)). The weight of stabilizer was determined by its analysis. Thus enough stabilizer was used to provide the same weight of combined tin as is provided by 2 parts of dibutyltin dilauryl mercaptide (0.374 part of Sn by weight). This was done in order to determine the relative merits of the various compounds.

The mixture was then milled for 5 minutes on a tworoll differential speed mill heated to 320-325 F. and removed as a sheet. Portions of the sheet were then placed in a single cavity mold (6" x 6" x 40 mils) preheated to 275 F. The mold was placed on a press and raised to 320 F. under 10,000 pounds total pressure. When the mold reached 320 F., the pressure was increased to 40,000 pounds and held until the temperature reached 330 F. This procedure required 5 to 5 /2 minutes. The mold and press platens were then cooled and the pressed sheet removed.

The pressed sheet was cut into 1" x 6" strips and placed in clips on a tray so that the strips would hang vertically. The tray was then placed in a circulating air oven held at 320 F. Samples were removed after one hour, two hours, three hours and four hours of heat aging. Samples were rated visually. Summary of the tests are indicated as follows:

Summary table [Codez e, colorless; vsy, very slight yellowing; sy, slight yellowing; y, yellowed; rbr, reddish brown; br, brown; bl, black; ble, black at edges] Appearance after heat aging 1 Hr. 2 Hrs. 3 Hrs. 4 Hrs.

Stabilizer from Example No.2

No stabilizer rbr bl Dibutyltin dilaurate (2 parts/ parts of resin)...- y rbr bl bl Example 1 vsy vsy sy Example 2 vsy vsy sy Example 3-.- vsy vsy sy Example 4..- sy sy y Example 5 vsy sy sy Example 6 sy y y Example 7 sy sy y Example 8..- vsy vsy sy Example 9..- sy sy sy Example 10 vsy sy sy Example 11 vsy sy sy Example 12 vsy vsy sy Example 12 in Geon 202 resin, 2. eopolymer of vinyl chloride and vinylidene dichloride sy sy sy sy Dibutyltin dilaurate in Geon 202 0y 0y bi bi Example l2 in VYNW resin, a eopolymer of vinyl chloride and vinyl acetate.. sy sy y rbr Dibutyltin dilaurate in VYNW resin 0y bl b1 bl Example 13 vsy vsy vsy sy Example 1 vsy vsy vsy sy vsy sy sy Example 23... Example 26.-. y y y y in Ultron 3 e e vsy y Example 27.. c vsy vsy sy Example 29--. c vsy sy y Example 30 ight gray tin in Ultron 300 Resin. vsy vsy sy sy Example 31--- vsy vsy vsy sy Example 32- vsy vsy sy sy Example 33 vsy vsy sy sy Example 34--- vsy vsy vsy sy Example 35---.- vsy vsy vsy vsy Example 36.--.. sy sy br Example 37 sy sy y y Further tests were carried out to determine the heat stability of vinyl films containing a phosphate plasticizer and stabilized with an organotin mercaptide of the present invention. The results of these tests are indicated in the table below. In this table, 0y indicates orange yellow, rb--red brown, and S-141 an aryl, alkyl phosphate plasticizer.

Film Composition 1 Hr. 2 Hrs. 3 Hrs. 4 Hrs.

VSY sy vsy 35 parts DOP parts 8-141 c 2 parts Dimethyltin di-tert-lauryi mercaptide.

vsy

C parts S141 di-lauryl mer- 2 parts Dibutyltin captide.

100 parts Geon 101 37.5 parts DOP 12.5 parts S14l y 2.0 parts Dibutyltin di-lauryl mercaptide.

For films containing phosphate plasticizers, the results shown are much better than would be obtained using other stabilizers. For example, using the formulation of film A but substituting 2 parts of dibutyltin dilaurate for two parts of dibutyltin dilauryl mercaptide, the results of the heat tests were: 1 hr.--oy; 2 hr.rbr; 3 hr.bl; 4 hr.--bl.

Tests were carried out to determine the stability of vinyl films to light when compounded with an organotin of the present invention. For that purpose, the films of 5 mils thickness were exposed to the accelerated light action of an Atlas Fadeometer. The results of these tests are as follows:

1 pt. Dimethyltin di-tertlauryl mercaptide. [100 pts. Geon 101 Specking at 600 SM. Fading, Hours. No onihrittlement and only slight general dis coloration at [.000 Std. Fading Hours.

10 pts. (3-25 1 pt. Dibutyltin dilauryl rnereaptide.

[100 pts. Geon 101 10 pts. G- I Like Film e. 1 pt. Diphenyltin dilouryl mercaptide.

100 pts. Geon 101 Like Film 6.

1 pt. Diarnyltin di-lauryl rnercaptide.

l Pomplcx a plasticizer made by Rolim and Haas and consisting essentially of polyesters.

Geon lOl, appearing in the tables above, is a homopolymer of vinyl chloride manufactured by the B. F. Goodrich Company. VYNW, appearing in the above tables, is a copolymer of 96% vinyl chloride and 4% vinyl acetate and is manufactured by Carbide and Carbon Chemicals Corporation. Geon 202 is a resin copolymer of vinyl chloride and vinylidine dichloride manufactured by the B. F. Goodrich Company.

While the invention has been described with particular reference to specific embodiments, it is to be understood thot it is not to be so limited thereto but is to be construed broadly and restricted solely by the scope of the appended claims.

8 What is claimed is: 1. A composition of matter comprising a halogen containing resin and a stabilizing amount of an organotin mercaptide of formula wherein R is an alkyl radical, and R is a radical selected from the class consisting of 2-aminophenyl and 2-benzothiazyl radicals, said halogen-containing resin being selected from the class consisting of homopolymers of vinyl chloride, copolymers of vinyl chloride and vinylidine dichloride, and copolymers of vinyl chloride and vinyl acetate containing 96% vinyl chloride and 4% vinyl acetate.

2. A composition according to claim 1 including a plasticizer.

3. A composition comprising a homopolymer vinyl chloride resin and a stabilizing amount of dibutyltin di(2- benzothiazyl) mercaptide.

4. A composition according to claim 3 including a plasticizer.

5. A composition according to claim 4 wherein the plasticizer is dioctylphthalate.

6. A composition comprising a homopolymer vinyl chloride resin and a stabilizing amount of dibutyltin di(2- aminophenyl) mercaptide.

7. A composition according to claim 6 including a plasticizer.

8. A composition according to claim 7 wherein the plasticizer is dioctylphtalate.

9. A process for the stabilization of a halogen containing resin composition comprising intimately dispersing therein a stabilizing amount of an organotin mercaptide of formula (R Sn(SR) wherein R is an alkyl radical and R is a radical selected from the class consisting of 2-aminophenyl and Z-benzothiazyl radicals, said halogen-containing resin being selected from the class consisting of homopolymers of vinyl chloride, copolymers of vinyl chloride and vinylidine dichloride, and copolymers of vinyl chloride and vinyl acetate containing 96% vinyl chloride and 4% vinyl acetate.

10. A process according to claim 9 wherein said halogen containing vinyl resin composition contains a plasticizer.

11. A process for the stabilization of a homopolymer vinyl chloride resin composition which comprises intimately dispersing therein a stabilizing amount of di butyltin di(2-benzothiazyl) mercaptide.

12. A process according to claim 11 wherein said homopolymer vinyl chloride resin composition contains a plasticizer.

13. A process according to claim 12 wherein said plasticizer is dioctylphthalate.

14. A process for the stabilization of a homopolymer vinyl chloride resin composition which comprises intimately dispersing therein a stabilizing amount of dibutyltin di(2-aminophenyl) mercaptide.

15. A process according to claim 14 wherein said homopolymer vinyl chloride resin composition contains a plasticizer.

16. A process according to claim 15 wherein the plas ticizer is dioctylphthalate.

References Cited in the file of this patent UNITED STATES PATENTS 2,726,227 Leistner et al. Dec. 6, 1955 2,731,440 Stefl et al. Jan. 17, 1956 2,731,441 Stefl et al. Jan. 17, 1956 2,731,484 Best Jan. 17, 1956 

1. A COMPOSITION OF MATTER COMPRISING A HALOGEN CONTAINING RESIN AND A STABILIZING AMOUNT OF AN ORGANOTIN MERCAPTIDE OF FORMULA 